On Sun, Oct 28, 2018 at 02:51:08PM +0000, Jonathan Cameron wrote:
> On Sun, 28 Oct 2018 13:23:23 +0530
> Nishad Kamdar <nishadkamdar@xxxxxxxxx> wrote:
>
> > Replace platform data with device tree support.
> >
> > Signed-off-by: Nishad Kamdar <nishadkamdar@xxxxxxxxx>
> The whole gpio in or out thing makes less and less sense to
> me and seems to contradict the datasheet.
>
> If I'm not missing something I would just get rid of the option.
> If I am missing something (not hard in the datasheet which, whilst
> fairly clear, is a rather long ;)
>
> Jonathan
>
Ok, I'll drop it.
> > ---
> > drivers/staging/iio/resolver/Kconfig | 1 +
> > drivers/staging/iio/resolver/ad2s1210.c | 17 ++++++++---------
> > drivers/staging/iio/resolver/ad2s1210.h | 17 -----------------
> > 3 files changed, 9 insertions(+), 26 deletions(-)
> >
> > diff --git a/drivers/staging/iio/resolver/Kconfig b/drivers/staging/iio/resolver/Kconfig
> > index 6a469ee6101f..cc1202ff813d 100644
> > --- a/drivers/staging/iio/resolver/Kconfig
> > +++ b/drivers/staging/iio/resolver/Kconfig
> > @@ -15,6 +15,7 @@ config AD2S90
> >
> > config AD2S1210
> > tristate "Analog Devices ad2s1210 driver"
> > + depends on OF
> > depends on SPI
> > depends on GPIOLIB || COMPILE_TEST
> > help
> > diff --git a/drivers/staging/iio/resolver/ad2s1210.c b/drivers/staging/iio/resolver/ad2s1210.c
> > index 0234869e9d74..5ecdb5785132 100644
> > --- a/drivers/staging/iio/resolver/ad2s1210.c
> > +++ b/drivers/staging/iio/resolver/ad2s1210.c
> > @@ -17,6 +17,7 @@
> > #include <linux/delay.h>
> > #include <linux/gpio/consumer.h>
> > #include <linux/module.h>
> > +#include <linux/of.h>
> >
> > #include <linux/iio/iio.h>
> > #include <linux/iio/sysfs.h>
> > @@ -76,7 +77,6 @@ struct ad2s1210_gpio {
> > };
> >
> > struct ad2s1210_state {
> > - const struct ad2s1210_platform_data *pdata;
> > struct mutex lock;
> > struct spi_device *sdev;
> > struct gpio_desc *sample;
> > @@ -84,6 +84,7 @@ struct ad2s1210_state {
> > struct gpio_desc *a1;
> > struct gpio_desc *res0;
> > struct gpio_desc *res1;
> > + bool gpioin;
> > unsigned int fclkin;
> > unsigned int fexcit;
> > bool hysteresis;
> > @@ -314,7 +315,7 @@ static ssize_t ad2s1210_store_control(struct device *dev,
> > }
> > st->resolution
> > = ad2s1210_resolution_value[data & AD2S1210_SET_RESOLUTION];
> > - if (st->pdata->gpioin) {
> > + if (st->gpioin) {
> > data = ad2s1210_read_resolution_pin(st);
> > if (data != st->resolution)
> > dev_warn(dev, "ad2s1210: resolution settings not match\n");
> > @@ -376,7 +377,7 @@ static ssize_t ad2s1210_store_resolution(struct device *dev,
> > }
> > st->resolution
> > = ad2s1210_resolution_value[data & AD2S1210_SET_RESOLUTION];
> > - if (st->pdata->gpioin) {
> > + if (st->gpioin) {
> > data = ad2s1210_read_resolution_pin(st);
> > if (data != st->resolution)
> > dev_warn(dev, "ad2s1210: resolution settings not match\n");
> > @@ -603,7 +604,7 @@ static int ad2s1210_initial(struct ad2s1210_state *st)
> > int ret;
> >
> > mutex_lock(&st->lock);
> > - if (st->pdata->gpioin)
> > + if (st->gpioin)
> > st->resolution = ad2s1210_read_resolution_pin(st);
> > else
> > ad2s1210_set_resolution_pin(st);
> > @@ -644,7 +645,7 @@ static int ad2s1210_setup_gpios(struct ad2s1210_state *st)
> > int ret, i;
> > struct spi_device *spi = st->sdev;
> > struct ad2s1210_gpio *pin;
> > - unsigned long flags = st->pdata->gpioin ? GPIOD_IN : GPIOD_OUT_LOW;
> > + unsigned long flags = st->gpioin ? GPIOD_IN : GPIOD_OUT_LOW;
> >
> > struct ad2s1210_gpio gpios[] = {
> > { .ptr = &st->sample, .name = "sample", .flags = GPIOD_IN },
> > @@ -673,16 +674,14 @@ static int ad2s1210_probe(struct spi_device *spi)
> > {
> > struct iio_dev *indio_dev;
> > struct ad2s1210_state *st;
> > + struct device_node *np = spi->dev.of_node;
> > int ret;
> >
> > - if (!spi->dev.platform_data)
> > - return -EINVAL;
> > -
> > indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
> > if (!indio_dev)
> > return -ENOMEM;
> > st = iio_priv(indio_dev);
> > - st->pdata = spi->dev.platform_data;
> > + st->gpioin = of_property_read_bool(np, "gpioin");
>
> Hmm. This bothered me in the earlier patch. How are we meant to configure
> these pins... (and this time I actually loaded the datasheet)
>
> A0 and A1 always seem to be control signals written to the device so
> I don't really understand why we would ever want them to be 'inputs'
> on our host.
>
> RES0 and RES1 are also control signals. Clearly marked as logic inputs.
>
> The only thing I can think here is there is an evaluation board out there
> were we are not in control of these, some other controller is.
> That is a pretty weird board if so, hence I would only support the version
> where we use GPIO outputs from the host.
>
> This will further simplify patch 1 and get rid fo the need for this
> non standard bit of devicetree binding.
>
>
> > ret = ad2s1210_setup_gpios(st);
> > if (ret < 0)
> > return ret;
> > diff --git a/drivers/staging/iio/resolver/ad2s1210.h b/drivers/staging/iio/resolver/ad2s1210.h
> > index 63d479b20a6c..e69de29bb2d1 100644
> > --- a/drivers/staging/iio/resolver/ad2s1210.h
> > +++ b/drivers/staging/iio/resolver/ad2s1210.h
> > @@ -1,17 +0,0 @@
> > -/*
> > - * ad2s1210.h plaform data for the ADI Resolver to Digital Converters:
> > - * AD2S1210
> > - *
> > - * Copyright (c) 2010-2010 Analog Devices Inc.
> > - *
> > - * This program is free software; you can redistribute it and/or modify
> > - * it under the terms of the GNU General Public License version 2 as
> > - * published by the Free Software Foundation.
> > - */
> > -#ifndef _AD2S1210_H
> > -#define _AD2S1210_H
> > -
> > -struct ad2s1210_platform_data {
> > - bool gpioin;
> > -};
> > -#endif /* _AD2S1210_H */
>
Ok, I'll make the changes.
Thanks for the review.
regards,
Nishad
